Rabbit model provides new insights in liver regeneration after transection with portal vein ligation

Abstract

Background: The rabbit model of associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has not been reported before.

Materials and methods: New Zealand white rabbits were allocated to two protocols. Protocol 1 involved either liver parenchymal transection (LPT, n = 5) or portal vein ligation (PVL, n = 5). Protocol 2 involved the ligation of different portal vein branches combined with liver partition, including the LPT + 20% PVL group (n = 5; the caudate portal vein was ligated), the LPT + 50% PVL group (n = 5; the left portal vein was ligated), and the LPT + 70% PVL group (n = 10; both veins were ligated). Computed tomography liver volumetry was performed immediately after operation. Blood samples were harvested before surgery and at days 1, 3, 7, or 14 after surgery for liver function evaluation. Most rabbits were humanely euthanized on day 7. The livers were harvested, divided into lobes, and weighed; biopsies of each lobe and immunohistochemical staining were performed.

Results: In this article, we present a new rabbit model to simulate ALPPS procedure, with a description of the regional anatomical features, surgical routes, and key techniques. The growth rate of remnant right lobe volume increased with proportionally PVL combined with LPT. Specifically, right lobe volume growth rate of the LPT + 50% PVL group overwhelmed 70% PVL alone.

Conclusions: There were putative underlying mechanisms other than portal inflow redistribution in triggering residual liver regeneration after ALPPS procedure. This rabbit model is feasible for further mechanism research of this special clinical phenomenon.

Keywords: Animal model; Ligation; Liver regeneration; Portal vein.